This invention relates to a combustion system for an internal combustion engine, particularly a fuel injected engine in which the period for mixing the fuel with air is extremely short inhibiting complete mixture and full combustion.
In the present state of the art of internal combustion engines, spark ignited engines and compression ignited engines are at opposite poles of thermal cycles when it comes to mixing the air and fuel and combusting the air-fuel mixture. In a conventional spark ignited engine, air and fuel are well mixed during aspiration or compression of the fuel air charge. Coupled with the higher volatility of gasoline in comparison with diesel fuel primarily used in compression ignited engines, relatively complete mixture and uniform combustion can be accomplished in gasoline engines. Difficulties arise in spark ignited engines where fuel injectors are timed to inject fuel during the final period of the compression stroke. In such situation the fuel injected gasoline engine may perform in a similar manner to conventional diesel engines with less than complete combustion.
In the conventional compression ignited engine, particularly the customary diesel engine, the fuel and air mixture is internally formed during the very last stages of compression. Because the fuel is directly injected as a liquid into the hot compressed air, incomplete combustion is inevitable with internal zones of low temperature, forming discharge of particulate carbon, and local zones of extremely high temperature, forming oxides of nitrogen.
Since conventional gasoline and diesel fuel engines are the predominant means of propelling vehicles of transportation, the engines are required to be operated under an extraordinarily wide range of conditions. Because of the inefficiencies of the mixture and ignition cycle and the required variable operating conditions, modern engines continue to be the major source of air pollution. Although the specific reasons for pollutant emissions in all of these engines are well known by those who are professionally skilled, and, although intensive research is being conducted throughout the world to solve or at least to diminish this major source of pollution, the problem of vehicle exhaust pollution remains. State of the art attempts at solving the problem act primarily outside of the combustion chamber using catalytic converters, particulate traps, after-combustors and other methods that act on the exhaust stream and not on the source of the problem, the combustion process. The combustion system of this invention is designed to resolve the problem of excessive air pollution by a fundamental change in the manner in which fuel is combusted in the combustion chamber.